The air sac at the flat end of an egg acts as a shock absorber and later provides air.
An egg can float in water if it is not fresh because as the egg ages, it loses moisture and air enters the shell, increasing its buoyancy. This causes the egg to float due to the air pocket inside it.
The bubble in the egg is called an air sac, and helps prevent the egg from drying out (too quickly).
the air sac itself.
The developing chick inside the egg needs air once its lungs develop, this reserve air sac allows the chick to breathe and gives them room to maneuver when it is time to peep (break out of the shell).
the egg sac keeps the egg safe and pervides and it food for the egg
There are five main part of a hens egg, the outer shell, the albumen or egg white, the yolk, there is a membrane between the albumen and the shell and an air space at the fat end of the egg.
A praying mantis egg sac typically contains around 100 to 200 eggs.
Every single site I've looked (including the Britannica Encyclopedia) calls it an "egg sac".
Charlotte laid eggs and made an egg sac to ensure that her legacy and friendship with Wilbur would continue after she died. The egg sac contained her offspring, which would eventually hatch and continue the cycle of life on the farm.
Just before hatching begins, the air cell expands to approximately 30% of the internal volume of the egg. As hatching begins, the beak of the embryo penetrates the inner shell membrane where it forms the inner wall of the air cell. The lungs begin to function, inhaling the air from the air cell.
The developing chick inside the egg needs air once its lungs develop, this reserve air sac allows the chick to breathe and gives them room to maneuver when it is time to peep (break out of the shell).